Aerial rockets and missiles which include guidance wings have been in use at least since the late 1940's, with the FFAR (Folding Fin Aerial Rocket) being used in the Korean and Vietnam conflicts, and the more recent Hydra 70 family of WAFAR (Wrap-Around Fin Aerial Rocket) and the Advanced Precision Kill Weapon. System (APKWS) laser guided missile. The guidance wings for these weapons are typically folded within the main fuselage in a stowed configuration until the weapon is launched, at which point the wings are extended through slots in the fuselage and deployed in a flight configuration.
While foldable wing designs provide the advantages of compact storage and reduced launcher size, the slots in the fuselage required for deployment of the wings tend to create a hazard that internal components of the weapon will be exposed to contaminants. These can include natural contaminants, such as salt, moisture from fog, moisture from humidity, blowing sand, blowing dust, and such like. The internal components can also be exposed to induced contaminants, such as debris from an adjacent rocket launch, and contaminants resulting from handling of the missile.
One approach is to provide retractable or openable covers over the wing slots. However, such mechanisms add weight and cost to the missile, take up space which may be needed for other components, and tend to be complex and prone to failure.
What is needed, therefore, is a wing slot seal which will protect the internal components of a rocket or missile from external contaminants while the wings are in their stowed configuration, will interfere as little as possible with deployment of the wings, and will not substantially affect the aerodynamics of the missile once the wings are deployed, all without consuming significant space and without adding significant weight, cost, complexity, or likelihood of failure.